The full video of the amp dyno test is on youtube now
Impressive!

Sure enough after basic testing I pulled the PS caps. There was hardly any trace of electrolytic fluid under the caps. They were so clean I actually felt bad after pulling them. But better safe than sorry and at least I have perfect solder pads to work with. One of the endplate screws was so tight i...

Finally I scored a nice old skool Phoenix Gold big rig MPS 2500 :D Dirty on the outside, but absolutely mint on the inside where it counts. I'm surprised it on only draws 1,2 amps of current idle. The rail voltages are nailed at only +-29V so this thing really wants to be loaded down to get the powa...

The problem is you can only put so many amps in a car. And even plenty amps in your car doesn't stop the craving..

Whats up with that box? I have never seen anything like it.

You dont have to replace the 4700uF caps, but you HAVE TO replace the 2200uF caps! They are the leaky ones eating away the board. And eventually the amp will short out under the caps and make lots of smoke and fire. Looks like the soldering is incomplete in the second picture. Theres probably some s...

If you snip some diodes off the amp then it will remain in high voltage mode even with a lower load than 4ohm bridged. If you do this then you run the risk of frying the amps power supply fets.
You might get away with 2ohms bridged however, if the sub is in a sealed box.

PS caps: panasonic eeu fc1c822

"Cost over £1500 new back in 1995
One of 0nly 1500 hand made ltd edition run"

????

There were no LE MS275 I think.

Okay, this is just an idea I had in my head and a little bit of fun. I spent 2 minutes "photoshopping" this with windows Paint and it looks even better than I thought. I can't stop smiling :D I have always loved the PG combination of white and gold, and this is just GOLD, ahh! But in truth...

ZPA cooling fans are a bit noisy. It's not a big deal when you're cruising and the ZPAs are putting out mind-numbing crazy dBz. But in principal the cooling fans aren't in line with the high end sound quality design of ZPAs. I have a ZPA which will probably always decorate my garage wall and also po...

I recapped this ZPA and gave it a little try. First thing I noticed is that the DC offset has changed from 11/15mV to about 30/50mV. This puzzles me, because I havent touched the bias pots. I did remove and reinstall the heat sinks. Also the fans werent connected when I measured DC offset. SO maybe ...

I've always thought ZXti amps are a bit cheesy for having ZeroPoint printed on their boards. I don't know of any ZeroPoint -kungfu incorporated in these amps and they sure can't handle no zero point anything ohm loads like ZPA:s. Hence their name. What I mean is ZXti:s are great amps in their own ri...

The input voltage range 10,5 to 15V refers to the power input voltage, not signal.

Are those extra rail caps in the middle? The wiring suggests they are.

Great info, thanks Eric! These ZPA amps confuse me, especially the power supply design. I wish I had the schematics. 30V RMS output capability is in line with the 200W @4ohm stereo specs you see here and there. But this means the rail voltage is at least 43V, yet the amp has 35V rail caps. Duh! All ...

Thanks for the concern and all the info, zeropoint! I take precautions when powering up an amp with old caps. I have an amp meter with a 10A fuse in it inline with the amp. This way I can see if it draws too much current and disconnect it. Also i use a tiny 12V 1,5Ah hand drill battery for powering ...

I scored a zpa0.3 for a good price. Its a bit banged up and rusty on the outside and the plexi is rubbish, of course. The insides are dusty but otherwise perfect. Main thing is no-one has tampered with it before me :clap: I powered the amp up to see it works. Idle current is 1,75A and DC offset 11mV...

Go for it. Install all three woofers and wire them (coils in series for 4ohm) in parallel for a 1,33 ohm final load and then bridge that. It should be fine. Woofers in a sealed box will have a higher impedance than nominal. In this case about 5 ohm minimum. And anyways an elite can handle just about...

According to the owners manual youre going to need two 4inch diameter ports for your box. One six inch diameter port would do the trick too. Lenght of ports should be 12 inches (each).

Personally I would use shorter ports, maybe 9 to 10 inches to get the tuning frequency a bit higher.

Adding two separating walls is worth the trouble, they will make the box much stiffer. If the woofers are wired in series, chances are they will have uneven output, so separate chambers is a good idea. I'm assuming the woofers are dual 2ohm. I would wire the coils in series and the woofers in parall...

And also you cannot substitute an amps power supply or rail caps. If you remove the power supply caps, the amp might work a while at low power levels. But the power supply would be starved for current because it would be pulling high frequency current through the filtering coil. And a coil acts as a...

Pendulum
Knife Party
-to name a few

I like checking out new stuff on youtube, especially now after finishing my new HT subwoofers

Freaky

Open the pod bay door please, Hal.